diff --git a/XPath/XPath.hpp b/XPath/XPath.hpp
index 65b3bf66..8cd65a39 100644
--- a/XPath/XPath.hpp
+++ b/XPath/XPath.hpp
@@ -20,7 +20,7 @@ xpath_execution_context.hpp
 xpath_expression.hpp
 xpath_function.hpp
 xpath_function_holder.hpp
-xpath_function_resolver.hpp
+DONE - xpath_function_resolver.hpp
 xpath_grammar.hpp
 xpath_logical.hpp
 DONE - xpath_namespace_context.hpp
diff --git a/XPath/impl/xpath_execution_context.hpp b/XPath/impl/xpath_execution_context.hpp
index b5ba0bf1..ea9f6afd 100644
--- a/XPath/impl/xpath_execution_context.hpp
+++ b/XPath/impl/xpath_execution_context.hpp
@@ -1,6 +1,7 @@
 #ifndef ARABICA_XPATH_EXECUTION_CONTEXT_HPP
 #define ARABICA_XPATH_EXECUTION_CONTEXT_HPP
 
+#include <Utils/StringAdaptor.h>
 #include "xpath_variable_resolver.hpp"
 #include "xpath_resolver_holder.hpp"
 
@@ -30,14 +31,14 @@ public:
 
   void setPosition(unsigned int pos) { position_ = pos; }
 
-  const VariableResolver<std::string>& variableResolver() const { return variableResolver_.get(); }
-  void setVariableResolver(const VariableResolver<std::string>& resolver) { variableResolver_.set(resolver); }
-  void setVariableResolver(VariableResolverPtr<std::string>& resolver) { variableResolver_.set(resolver); }
+  const VariableResolver<std::string, Arabica::default_string_adaptor<std::string> >& variableResolver() const { return variableResolver_.get(); }
+  void setVariableResolver(const VariableResolver<std::string, Arabica::default_string_adaptor<std::string> >& resolver) { variableResolver_.set(resolver); }
+  void setVariableResolver(VariableResolverPtr<std::string, Arabica::default_string_adaptor<std::string> >& resolver) { variableResolver_.set(resolver); }
 
 private:
   size_t position_;
   size_t last_;
-  ResolverHolder<const VariableResolver<std::string> > variableResolver_;
+  ResolverHolder<const VariableResolver<std::string, Arabica::default_string_adaptor<std::string> > > variableResolver_;
 
   ExecutionContext(const ExecutionContext&);
   ExecutionContext& operator=(const ExecutionContext&);
diff --git a/XPath/impl/xpath_parser.hpp b/XPath/impl/xpath_parser.hpp
index 4ba3558a..90478c36 100644
--- a/XPath/impl/xpath_parser.hpp
+++ b/XPath/impl/xpath_parser.hpp
@@ -87,10 +87,10 @@ public:
   const NamespaceContext<string_type, string_adaptor>& getNamespaceContext() const { return namespaceContext_.get(); }
   void resetNamespaceContext() { namespaceContext_.set(NamespaceContextPtr<string_type, string_adaptor>(new NullNamespaceContext<string_type, string_adaptor>())); }
 
-  void setVariableResolver(const VariableResolver<string_type>& variableResolver) { variableResolver_.set(variableResolver); }
-  void setVariableResolver(VariableResolverPtr<string_type> variableResolver) { variableResolver_.set(variableResolver); }
-  const VariableResolver<string_type>& getVariableResolver() const { return variableResolver_.get(); }
-  void resetVariableResolver() { variableResolver_.set(VariableResolverPtr<string_type>(new NullVariableResolver<string_type>())); }
+  void setVariableResolver(const VariableResolver<string_type, string_adaptor>& variableResolver) { variableResolver_.set(variableResolver); }
+  void setVariableResolver(VariableResolverPtr<string_type, string_adaptor> variableResolver) { variableResolver_.set(variableResolver); }
+  const VariableResolver<string_type, string_adaptor>& getVariableResolver() const { return variableResolver_.get(); }
+  void resetVariableResolver() { variableResolver_.set(VariableResolverPtr<string_type, string_adaptor>(new NullVariableResolver<string_type, string_adaptor>())); }
 
   void setFunctionResolver(const FunctionResolver<string_type, string_adaptor>& functionResolver) { functionResolver_.set(functionResolver); }
   void setFunctionResolver(FunctionResolverPtr<string_type, string_adaptor> functionResolver) { functionResolver_.set(functionResolver); }
@@ -136,7 +136,7 @@ private:
   xpath_grammar_expr xpathge_;
 
   ResolverHolder<const NamespaceContext<string_type, string_adaptor> > namespaceContext_;
-  ResolverHolder<const VariableResolver<string_type> > variableResolver_;
+  ResolverHolder<const VariableResolver<string_type, string_adaptor> > variableResolver_;
   ResolverHolder<const FunctionResolver<string_type, string_adaptor> > functionResolver_;
 
   /////////////////////////////////////////////////////////////////////////////////
diff --git a/XPath/impl/xpath_variable_resolver.hpp b/XPath/impl/xpath_variable_resolver.hpp
index bd36f21b..b191fba3 100644
--- a/XPath/impl/xpath_variable_resolver.hpp
+++ b/XPath/impl/xpath_variable_resolver.hpp
@@ -15,7 +15,7 @@ public:
   UnboundVariableException(const std::string& thing) : std::runtime_error("The variable '" + thing + "' is undefined.") { }
 }; // class UnboundVariableException
 
-template<class string_type>
+template<class string_type, class string_adaptor>
 class VariableResolver
 {
 public:
@@ -24,20 +24,23 @@ public:
   virtual XPathValuePtr<string_type> resolveVariable(const string_type& name) const = 0; 
 }; // class VariableResolver
 
-template<class string_type>
-class VariableResolverPtr : public boost::shared_ptr<VariableResolver<string_type> >
+template<class string_type, class string_adaptor>
+class VariableResolverPtr : public boost::shared_ptr<VariableResolver<string_type, string_adaptor> >
 {
 public:
-  explicit VariableResolverPtr(VariableResolver<string_type>* vr) : boost::shared_ptr<VariableResolver<string_type> >(vr) { }
+  explicit VariableResolverPtr(VariableResolver<string_type, string_adaptor>* vr) : 
+      boost::shared_ptr<VariableResolver<string_type, string_adaptor> >(vr) 
+  { 
+  } // VariableResolverPtr
 }; // class VariableResolverPtr
 
-template<class string_type>
-class NullVariableResolver : public VariableResolver<string_type>
+template<class string_type, class string_adaptor>
+class NullVariableResolver : public VariableResolver<string_type, string_adaptor>
 {
 public:
   virtual XPathValuePtr<string_type> resolveVariable(const string_type& name) const
   {
-    throw UnboundVariableException(name);
+    throw UnboundVariableException(string_adaptor().asStdString(name));
   } // resolveVariable
 }; // NullVariableResolver
 
diff --git a/test/XPath/execute_test.cpp b/test/XPath/execute_test.cpp
index d406a181..8433c8f4 100644
--- a/test/XPath/execute_test.cpp
+++ b/test/XPath/execute_test.cpp
@@ -10,7 +10,7 @@
 
 using namespace Arabica::XPath;
 
-class StringVariableResolver : public VariableResolver<std::string>
+class StringVariableResolver : public VariableResolver<std::string, Arabica::default_string_adaptor<std::string> >
 {
 public:
   virtual XPathValuePtr<std::string> resolveVariable(const std::string& name) const
@@ -31,7 +31,7 @@ private:
   VarMap map_;
 }; // StringVariableResolver
 
-class NodeSetVariableResolver : public VariableResolver<std::string>
+class NodeSetVariableResolver : public VariableResolver<std::string, Arabica::default_string_adaptor<std::string> >
 {
 public:
   virtual XPathValuePtr<std::string> resolveVariable(const std::string& name) const